Launch files#

Overview#

Autoware uses the ROS 2 launch system to start the software. Please see the official documentation to get a basic understanding about ROS 2 Launch system if you are not familiar with it.

Guideline#

The organization of launch files in Autoware#

Autoware distinguishes between the reusable node implementations and their example integration, including system-specific configurations, pipelines, and system topologies.

• Reusable node implementations can be found in autoware_core and autoware_universe
  • autoware_core repository itself provides a minimal integration in the package named autoware_core.
• An integrated system example orchestrated from these nodes can be found in autoware_launch.
  • There are many possible ways to construct a full autonomous driving system, and autoware_launch provides one, highly configurable reference integration.

The autoware_launch repository (version 0.53.0 in Autoware 2.0.0) contains these packages:

• autoware_launch: the entry points and the component launch files in launch/components.
• autoware_universe_launch/autoware_<component>_launch: the launch files of each component, for example autoware_localization_launch.
• autoware_universe_launch/autoware_<component>_config: the parameter files of each component, for example autoware_localization_config.
• tier4_universe_launch/tier4_<name>_launch: the launch files of the system, the API, the simulator, and the vehicle.
• sensor_kit/<name>_sensor_kit_launch: the launch and description packages of each sensor kit, for example sample_sensor_kit_launch and sample_sensor_kit_description.
• vehicle/<name>_vehicle_launch: the launch and description packages of each vehicle, for example sample_vehicle_launch and sample_vehicle_description.
• autoware_sample_designs: an example that defines the system with Autoware System Designer and generates the launch files from it.

The package autoware_launch itself provides the general entrypoint to call other modularized launch files and start the Autoware nodes.

• The autoware.launch.xml is the basic launch file for road driving scenarios.

  This launch file loads other launch files for different modules, including Vehicle, System, Map, Sensing, Localization, Perception, Planning, Control, etc. By setting the launch_* argument to either true or false , the users can selectively load a subset of the system.

• The logging_simulator.launch.xml is often used together with the recorded ROS bag to debug if the target module (e.g, Sensing, Localization or Perception) functions normally.

• The planning_simulator.launch.xml is based on the Planning Simulator tool, mainly used for testing/validation of Planning module by simulating traffic rules, interactions with dynamic objects and control commands to the ego vehicle.

• The e2e_simulator.launch.xml is the launcher for digital twin simulation environment. Its simulator_type argument selects AWSIM (awsim, the default) or CARLA (carla).

The next diagram shows how these launch files include each other, with the localization component as an example. The names are from autoware_launch 0.53.0.

Add a new package in Autoware#

If a newly created package has executable node, we expect example launch files and configurations within the package, just like the recommended structure shown in the previous directory structure page.

Integrate a new package in autoware_launch#

In order to automatically load the newly added package (in autoware_core or autoware_universe) when starting Autoware, you need to make some necessary changes to the corresponding launch file.

For example, to add a node to the localization component:

1. Include the launch file of your package from the correct launch file in autoware_universe_launch/autoware_localization_launch/launch. Some node packages are included directly from autoware_launch/launch/components/component_localization.launch.xml, for example autoware_pose_estimator_arbiter.
2. Add the launch parameter file of your node to autoware_universe_launch/autoware_localization_config/config, and pass its path to your launch file.
3. Register the pair of the node parameter file and the launch parameter file in the sync-params configuration. See sync-params.

Parameter and system topology management#

Another purpose of introducing the autoware_launch repository is to facilitate the parameter and system topology management of Autoware.

Suppose that we want to integrate Autoware based on autoware_launch to a specific vehicle, and that we are only interested in different parameters and possibly different node configurations, without rewriting the existing node implementations. In such case, we can fork only autoware_launch to customize the parameters or the pipelines, without modifying the official autoware_universe.

Taking the localization module as an example, in the autoware_launch repository:

1. all the launch parameter files for the localization component are in autoware_universe_launch/autoware_localization_config/config.
2. autoware_launch/launch/components/component_localization.launch.xml has the localization_config_pkg argument. It names the package that holds the parameter files. The default is autoware_localization_config.
3. in autoware_universe_launch/autoware_localization_launch/launch, the launch files make the parameter file paths from localization_config_pkg, for example the ekf_localizer_param_path argument of pose_twist_fusion_filter.launch.xml. They give these paths to the launch files of the node packages. You can still use the default parameters in each package, because the launch file of each node package has a default parameter file.

To use your own parameter files for all the localization nodes, set localization_config_pkg to your own package with the same config/ layout. To change only a few files, override the *_param_path arguments.

See sync-params to learn how these launch parameter files can be updated.